Convertible roller way conveyor

ABSTRACT

The roller way conveyor system of the present invention provides for the transport of articles supported on two inclined runs of freely rotatable horizontal axis rollers from one end to the other end, and the conveying of articles unsuited for support between the roller runs on a plurality of pipes freely supportable on and extending between the roller runs. Preferably, the pipes and rollers are freely journaled to provide solely for gravity conveying of articles carried thereon, and axial restraint means or confining means are provided to limit the axial movement of the pipes when supported on the rollers and to correspondingly limit the axial movement of articles supported on either the rollers or pipes. The rollers are equipped with elastomer tires having hysteresis properties so that there will be a controlled speed for conveyed articles, an accommodation of uneven article surfaces, quieter operation, and a firm adapting support of the pipes.

United States Patent 11 1 Tabler Oct. 30, 1973 1 CONVERTIBLE ROLLER WAYCONVEYOR [75] Inventor: Charles P. Tabler, Hamilton, Ohio [73] Assignee:Kornylak Corporation, Hamilton,

Ohio [22] Filed: Mar. 10, 1972 21 Appl. No.2 233,691

3,176,828 4/1965 Sullivan....... 3,263,797 8/1966 Lutes 198/127 RFOREIGN PATENTS OR APPLICATIONS 626,874 7 1949 Great Britain 198/2021,264,575 5/1961 France 193/35 R Primary Examiner-Richard AegerterAttorney-Thomas E. Beall, Jr.

[57] ABSTRACT The roller way conveyor system of the present inventionprovides for the transport of articles supported on two inclined runs offreely rotatable horizontal axis rollers from one end to the other end,and the conveying of articles unsuited for support between the rollerruns on a plurality of pipes freely supportable on and extending betweenthe roller runs. Preferably, the pipes and rollers are freely joumaledto provide solely for gravity conveying of articles carried thereon, andaxial restraint means or confining means are provided to limit the axialmovement of the pipes when supported on the rollers and tocorrespondingly limit the axial movement of articles supported on eitherthe rollers or pipes. The rollers are equipped with elastomer tireshaving hysteresis properties so that there will be a controlled speedfor conveyed articles, an accommodation of uneven article surfaces,quieter operation, and a firm adapting support of the pipes.

9 Claims, 7 Drawing Figures CONVERTIBLE ROLLER WAY CONVEYOR BACKGROUNDOF THE INVENTION Applicants prior gravity type roller way conveyors, asshown in U.S. Pat. No. 3,057,448, issued Oct. 9, 1962, and U.S. Pat. No.3,443,674, issued May 13, 1969, have provide to be extremely useful inthe conveying of various types of articles, under controlled speed,including pallets having uneven, discontinuous, and often timesdefective under surfaces. However, such parallel roller run conveyorshave the inherent disadvantage that they cannot convey relatively smallarticles that do not transversely extend between the roller runs, andthey cannot convey articles having sharp rims, which rims would fallbetween adjacent rollers, for example. However, they are light weightand open, which is desirable and can normally carry most tyes ofarticles that are to be conveyed. However, there has been nosatisfactory solution to the abovementioned problems without resortingto an entirely different type of conveyor, which would do away with theknown advantages of the parallel roller run type .of conveyor of theabove-mentioned patents.

It is further known to provide a single run of parallel axis rolls inthe construction of a conveyor, as shown by the Thomas U.S. Pat. No.896,172, issued Aug. 18, 1908. This type of conveyor has considerableadvantages with respect to the conveying of articles having very littletransverse dimension, but does not have the advantages of the parallelrun type of conveyor abovementioned.

SUMMARY OF THE INVENTION It is an object of the present invention toovercome the above-mentioned disadvantages of the parallel roller runtype of conveyor for conveying articles otherwise unsuited, by providingfor the conversion of the parallel roller run conveyor into a conveyorwith a single run of rolls. The rolls are freely supported at oppositeends on adjacent ones of the rollers of the respective roller runs, andrestrained in the axial direction by means of guide rails, interengagingflanges and the like.

Preferably, the rollers of the parallel runs are provided withelastomeric tires for the known advantages with respect to their usagein a parallel run type of conveyor, and to control the speed of articlescarried by the rolls on conversion, as well as to allow forirregularities in the articles and rolls that would tend to call for adifferential vertical movement between adjacent supporting rolls.

BRIEF DESCRIPTION OF THE DRAWING Further objects, features andadvantages of the present invention will become more clear from thefollowing detailed description of the drawing, wherein:

FIG. 1 is a partial perspective view of a portion of the conveyor systemaccording to one embodiment of the present invention;

FIG. 2 is a partial cross sectional view taken along line 22 of FIG. 1;

FIG. 3 is an end view of a second embodiment according to the presentinvention;

FIG. 4 is a partial cross sectional view taken along line 4-4 of FIG. 3;

FIG. 5 is a detailed partial end view of a roll and roller mountingusable with either the embodiment of FIG. I or FIG. 3;

FIG. 6 is a partial end view of a roll and roller mounting usable witheither the embodiment of FIG. 1 or FIG. 3; and

FIG. 7 is a partial end view of a roll and roller mounting usable witheither the embodiment of FIG. 1 or FIG. 3.

DETAILED DESCRIPTION OF THE DRAWING The embodiment of the conveyorsystem shown in FIG. 1 includes a frame structure of any appropriatetype, and may include, for example, vertical upright supports 1,transverse supports 2 carried on the vertical supports 1, side railsupports 3 carried on the opposite ends of the transverse supports 2,and longitudinal rail supports 4, all of which may be constructed ofmetal and bolted or welded together. The above framework is set forth byway of example only, and it is understood that any other suitable typeof framework may be employed.

A run 5 of horizontal axis rollers is mounted on one of the longitudinalrail supports 4 and parallel to a cooperating run 6 of horizontal axisrollers mounted on the other longitudinal rail support 4. While each ofthese runs include longitudinally aligned single rollers, as shown inapplicants above-mentioned U.S. Pat. No. 3,057,448, it is alsocontemplated that each of the runs may be of the heavier duty typeemploying two sets of longitudinally aligned rollers as set forth inapplicants above-mentioned U.S. Pat. No. 3,443,674. The disclosure ofthese two patents is incorporated herein in its entirety by reference.By way of a specific example, with runs 5 and 6 being identical, the run5 is constructed of two opposed roller support rails 7, 8 rigidlymounted in spaced relationship from each other and receiving theopposite ends of roller shafts 9 freely rotatably mounting thereonrespective rollers 10.

To generally longitudinally guide and prevent articles from transverselymoving off of the conveyor, side article guiding rails l1, 12 aresupported on the side rail supports 3 in generally parallel relationshipwith the runs 5, 6. Preferably, these side rails ll, 12 are providedwith a plurality of vertical axis rollers 13, to provide an antifrictionengagement with the sides of articles being conveyed.

Most preferably, the roller runs 5, 6 are inclined slightly downwardlyin the conveying direction with respect to the horizontal, for conveyingarticles solely by gravity. As more fully set forth in applicantsabovementioned patents, the roller runs 5, 6 will readily supportarticles having transverse dimensions at least as great as the generallyfixed spacing between the runs 5, 6, for example industrial pallets,large boxes, and crates. Such will be set up for normal operation andthe conveying of the majority of articles. However, there are manyarticles that do not lend themselves to this type of conveying. Forexample, their transverse dimensions may be insufficient to span thenormal spacing of the runs 5, 6, and it may be impractical to reduce thespacing between the runs to accommodate such articles, for example thebox 14 whose longest dimension is less than the dimension between theruns 5, 6. Further, even if the spacing between the runs 5, 6 wasadjustable over a wide range, there are certain articles such as thsmall can 15 that is so small in transverse dimension that it would beimpractical to reduce the spacing between the runs 5, 6 to accommodatesuch an article and further there would be the very real possibility ofthe article falling off of the conveyor to the right or left since therewould be considerable spacing between the side rails 11, 12 and theirimmediate adjacent runs 5, 6 with such a set up to accommodate the can15. Further, many large metallic barrels and the like 16 have relativelysharp rims 17 at their opposite ends; although such large barrels 16 mayhave a transverse dimension quite large and suitable for support betweenruns 5, 6 the nature of the sharp rim 17 would be such that it wouldfall between adjacent rollers and prevent the conveying of the barrel.It is the above types of articles that cannot satisfactorily be conveyedon the above-described parallel run conveyor more fully disclosed inapplicants above-mentioned patents.

According to the system of the present invention, the parallel rungravity roller way conveyor abovedescribed is convertible to a singlerun roll conveyor as shown in the drawings by providing a plurality ofgener ally equal length pipes or rolls mountable on the rollers 10 in agenerally inclined plane. Preferably, these rolls 18 are cut to equallengths from stock lengths of pipe so as to have uniform diameter andthickness throughout their entire axial extent. Using such stockmaterial, the rolls may be provided quite cheaply and are easilyreplaceable. As shown in FIG. 1, the left hand end of each roll 18 issupported between adjacent rollers 10 of the roller run 6, and the righthand end of each roll 18 is supported between adjacent rollers 10 on therollers run 5. The diameters of the rolls 18, which are equal, thediameters of the rollers 10, which are equal, and the spacing betweenthe shafts 9 are such that the rolls 18 are in firm driving engagementwith the rollers 10 and vertically spaced above the roller support rails7, 8. Thus it is seen that the rolls 18 are freely rotatable andsupported solely by the freely rotatable rollers 10.

In the above manner, the rollers 18 provide a support surface for theabove-mentioned types of articles 14, 15, 16 and many others. As morefully shown in FIG. 2, the side rails 11 vertically overlap, to somedegree, the rollers 18 so as to limit their axial movement at leastsufficiently so that they will not become disengaged with the rollers 10at either end.

Further, the side rails ll, 12, with their vertical axis rollers 13,extend vertically above the rolls l8 sufficiently to perform theirguiding function for the articles 14-16 being conveyed.

It is thus a simple and inexpensive procedure to convert the parallelrun roller way conveyor of the applicants above-mentioned patents into asingle run roll conveyor according to the present invention using onlystandard and readily available components with a minimum of effort. Thepipes or rolls 18 may thereafter be removed or readily stored or thrownaway due to their being so inexpensive when it is desired to reconvertthe conveyor into a parallel run roller way conveyor.

The embodiment of FIGS. 3 and 4 is quite similar to the previouslydescribed embodiment of FIGS. 1 and 2, so that like numerals will beemployed for like components and references made to the abovedescription for such common components. Unlike FIG. 1, the side rails11', 12' of FIG. 3 provide unbroken side vertical guide surfaces for thearticles, that is, there are no vertical axis rollers 13 on the siderails as in FIG. 1. A further difference between the two embodimentslies in the construction of the rollers 10, which may be provided withelastomeric or resilient tires 19, which provide the sole engagingsurface for the rolls 18'. Further, it is to be understood that therollers 10 of FIG. 1 also may be constructed with elastomeric tires.Such elastomeric tires are more fully set forth in applicantsabovementioned patents, with the resiliency of the elastomeric materialpreferably being within the range of a Shore durometer hardness of from60 to A. Preferably, the hardness of the elastomeric material will bechosen according to the expected load to be encountered. With heavierloads, it is desirable to have a greater hardness for the tire material.

Instead of relying upon the side rails 11, 12 or 11, 12' to axiallyconfine the rolls or pipes 18', the present invention furthercontemplates the special forming of the rolls 18, 18 with an annulargroove 20 at each end, which may be formed by rolling, milling,grinding, or the like. This groove 20 will preferably register in aguiding manner with the rollers 10, 10 of a mounting channel 21, toprovide for axial movement of the roll 18, 18' only to the extent of thedifference in transverse dimension between the groove 20 and roller 10.Further, it is contemplated that the groove 20 may be replaced by merelya reduced diameter end portion for the rolls 18, 18. While such aconstruction will allow the side rails 11, 12, 11', 12' to be spacedvertically higher than as shown in FIGS. 1-4 to more securely guidearticles carried by the conveyor, the construction of FIG. 5 has thedisadvantage that the rolls 18, 18 must be specially formed, that is,they cannot be merely cut lengths of standard pipe.

To reduce vibrations and noises, as well as to accommodate manufacturingtolerances, the roller support rails 7, 7, 8, 8' of FIGS. 1-4 preferablyhaving the mounting as shown in FIG. 5, wherein, elastomeric material 22is supportingly inserted between one of the roller support rails and themounting channel or rail 21. Such a mounting is more fully shown inapplicants above-mentioned US. Pat. No. 3,057,448.

As a further variation of the confining means for the rolls 18, 18',FIG. 6 employs a flange 23 formed by rolling, welding or the likeintegrally on each end of each roll 18, 18' so that it will verticallyoverlap the rollers 10, 10' to prevent axial movement of the rolls 18,18' beyond a predetermined range. FIG. 7 shows a variation identical inuse and description to that of FIG. 6, but employing a flange 24 to theinside of the roller l0, 10 for each end of the rolls .18, 18'.

The operation of the above conveyors either according to theabove-mentioned patents or for the conveying of articles of the typeshown at 14-16 in FIG. 1 has been described along with the appropriatestructure for conversion between the two types of conveyors. Further,the method of conversion has likewise been set forth during thedescriptive portion of the specification.

The elastomeric tires are of particular importance in supporting therolls 18, 18 for the following reasons. With the usage of standardpiping, the elastic engaging surface of the rollers will accommodatemanufacturing imperfections, dirt, misalignment, and surfaceimperfections resulting from misuse. Thus, the conveyor system operatingwith the rolls 18, 18' will have considerably less vibration and noisethan would be the case with hard surfaced rollers. Further, theelastomeric tired surface for the rollers will provide for placement ofthe rolls on the rollers so that there will be acute angle between theparallel axes of the rolls and the parallel axes of the rollers, whichmay be desirable to convey articles generally in the conveying directionperpendicular to the axes of the rollers, while moving such articles toone side of the conveyor against the appropriate side rail for automaticprocessing or the like. With elastic tired rollers, there will becontact across the full transverse dimension of the roller surfaces,whereas with inelastic surface rollers, there would be only rim contactor edge contact.

A further advantage of the elastic tired rollers in combination with therolls, is that articles having nonplanar support surfaces may be morereadily conveyed than if the rolls were supported on inelastic rollers.let it be assumed that a load having a plurality of narrow support railsgenerally parallel to and of a dimension to extend between the rolls isto be conveyed. With inelastic rollers supporting the rolls, the narrowrails will strike the rolls and be required to ride up over the rolls,which will have the effect of either stopping the load by thisinterference or requiring an inclination of the conveyor system so greatthat for smooth support surface articles the conveying speed would beintolerable. With the combination of the present invention, the rolls orpipes when struck would move downwardly correspondingly deforming theirelastic support surface provided by the elastomeric tires of therollers; the inertia of the rollers will be considerably less than heavyarticles, for example articles weighing from 1,000 to 14,000 lbs., sothat it is seen the operation with the combination of the presentinvention will be far smoother and not require great inclinations.Further, many industrial pallets although having bottom rails parallelto the support rolls would have defective rails, particularly when madeof wood that may be warped or split downwardly to provide a single edgeconsiderably lower than the general support plane for the pallet, whichedge would have the problems mentioned immediately above to be overcomeby the present invention with the rolls moving downwardly deformingtheir elastic support.

If the rolls were inelastically supported on inelastic or rigid rollers,there would be an uncontrolled buildup of speed for articles as theymove down the gravity conveyor, with such speed increasing with thelength of the conveyor.

This would present a considerable problem in that if the inclinationwere reduced the articles may hang up at the beginning of the conveyor,whereas if the inclination were increased, the speed at the end of theconveyor may result in damage of equipment or articles being conveyed,as well as danger to operating personnel in the vicinity. This can be aparticular problem when it is realized that single articles as heavy as14,000 lbs. may be conveyed with the system according to the presentinvention.

There is a further characteristic of the resilient support for the rigidrolls or pipes, in that energy will be consumed by the deformation ofthe elastomeric tires as they deform under the load transferred to themby the rigid pipes. Such may provide a hysteresis control that will tendto move articles along the conveyor within a narrow range of speed,which will change only slightly with relatively great changes in theweight of articles being conveyed. If articles are given a shove at theupper end of the conveyor to provide an initial speed greater than thisrange, the hysteresis effect will reduce the speed of the articles, andsimilarly if the articles start out at a speed lower than the speedrange, the

speed of the article will quickly be brought up to the desired range andthereafter remain substantially constant. in contrast, if the rollerswere provided with a hard inelastic surface for supporting the inelasticrigid rolls, the speed of travel for the articles down the conveyorwould increase substantially the entire length of the conveyor, and thedifferences in speed resulting in substantially different weight changesof articles being conveyed would be quite dramatic.

It is estimated that due to this hysteresis effect, the 30 feet perminute speed of an empty pallet for a typical conveyor would be reducedto approximately 10 feet per minute for a thousand pound load,approximately 5 feet per minute for a 4,000 pound load, andapproximately 3 feet per minute for a 9,000 pound load, and with verylittle change in speed with increased load thereafter, at least up tofifteen thousand pounds. In contrast, for a similar conveyor constructedwithout the resilient tires, that is with inelastic or rigid rollers androlls, it is estimated that the one thousand pound load would reach aspeed of approximately 240 feet per minute and heavier loads wouldcorrespondingly increase in speed, with the above-estimated figuresbeing for a 40 foot long conveyor system. With this built in speedcontrol, there will be less damage to articles being conveyed and therewill be no need for expensive stops, breaks, and the like.

While preferred embodiments of the present conveyor system have been setforth along with variations, further embodiments, modifications, andvariations are contemplated within the spirit and scope of the presentinvention as defined by the following claims.

What is claimed is:

l. A gravity conveyor roller way, comprising: at least two parallelsupport rails horizontally spaced from each other a predetermineddistance and inclined a small acute angle with respect to thehorizontal; a plurality of parallel, horizontal axis undriven wheelsjournaled for free rotation along each of said support rails, each ofsaid wheels having an outer annular elastomeric tire with highhysteresis and low coefficient of restitution properties; means fortransfering the load of articles between said rails to said wheels andthe free rotation of said wheels to the articles including a pluralityof generally parallel cylindrical rolls of substantially the same lengthat least greater than the predetermined distance between said supportrails, each of said rolls being solely supported at one end between apair of adjacent ones of said freely journaled wheels on one of saidsupport rails and being solely supported at its opposite end between acorresponding pair of adjacent ones of said freely journaled wheelsmounted on the other of said support rails, and each of said rolls beingsolely supported by direct engagement with said high hysteresiselastomeric tires; the top surfaces of said rolls generally lying in asupport plane inclined at said acute angle with respect to thehorizontal; and means confining the axial movement of said rolls to apredetermined range sufficiently small to maintain said rolls fullysupported at both ends on said wheels; said rolls and said wheelsconstituting means for moving articles soley by gravity horizontally anddownwardly generally parallel with said rails; speed control meansincluding said high hysteresis elastomeric tires for increasing thespeed of articles being gravity conveyed on said rolls up to apredetermined narrow speed range; said speed control means furtherdecreasing the speed of articles being gravity conveyed on said rolls tosaid predetermined speed range by converting the kinetic energy of thearticles above said predetermined narrow speed range to heat by the highhysteresis properties of said tires; and said speed control meansfurther decreasing the speed of articles within said predeterminednarrow speed range as the weight of the articles increases.

2. The gravity conveyor of claim 1, wherein said rolls are each ofuniform diameter and thickness throughout their entire length.

3. The gravity conveyor of claim 1, wherein said tires have shoredurometer hardness of from 60 to 85A.

4. The gravity conveyor of claim 1, wherein said confining means includeopposed side rails substantially parallel to each other and said supportrails, and each of said rails abuttingly overlapping, in the verticaldirection, each of said rolls and extending upwardly beyond said pipes asufficient distance to guide articles carried on said rolls.

5. The gravity conveyor of claim 4, including a plurality of verticalaxis free rollers mounted in alignment with each other completely abovesaid rolls and in said side guide rails to extend inwardly therefrom forengaging the sides of articles carried on said rolls.

6. The gravity conveyor of claim 1, wherein said confining meansincludes an outer annular groove within each of said rolls at each endthereof and spaced to coincide with the spacing of the supporting wheelsso that the wheels riding in the grooves act to prevent lateral movementof the rolls.

7. The gravity conveyor of claim 6, wherein said side support rails eachincludes parallel and outwardly horizontally opening U-shaped sidechannel members mounting therebetween said wheels, and at least oneU-shaped horizontally opening mounting channel receiving therein one ofsaid side channel members; and elastomeric means supportingly betweensaid one side channel and said mounting channel.

8. The gravity conveyor of claim 1, wherein said confining means includean annular flange integrally on each end of each of said rolls, each ofsaid annular flanges extending downwarldy to cooperate with one side ofeach of the supporting wheels.

9. The gravity conveyor of claim 1, wherein said speed control meansproduces the narrow speed range of three feet per minute for a 9,000pound load and 30 feet per minute for an empty pallet load.

1. A gravity conveyor roller way, comprising: at least two parallelsupport rails horizontally spaced from each other a predetermineddistance and inclined a small acute angle with respect to thehorizontal; a plurality of parallel, horizontal axis undriven wheelsjournaled for free rotation along each of said support rails, each ofsaid wheels having an outer annular elastomeric tire with highhysteresis and low coefficient of restitution properties; means fortransferring the load of articles between said rails to said wheels andthe free rotation of said wheels to the articles including a pluralityof generally parallel cylindrical rolls of substantially the same lengthat least greater than the predetermined distance between said supportrails, each of said rolls being solely supported at one end between apair of adjacent ones of said freely journaled wheels on one of saidsupport rails and being solely supported at its opposite end between acorresponding pair of adjacent ones of said freely journaled wheelsmounted on the other of said support rails, and each of said rolls beingsolely supported by direct engagement with said high hysteresiselastomeric tires; the top surfaces of said rolls generally lying in asupport plane inclined at said acute angle with respect to thehorizontal; and means confining the axial movement of said rolls to apredetermined range sufficiently small to maintain said rolls fullysupported at both ends on said wheels; said rolls and said wheelsconstituting means for moving articles soley by gravity horizontally anddownwardly generally parallel with said rails; speed control meansincluding said high hysteresis elastomeric tires for increasing thespeed of articles being gravity conveyed on said rolls up to apredetermined narrow speed range; said speed control means furtherdecreasing the speed of articles being gravity conveyed on said rolls tosaid predetermined speed range by converting the kinetic energy of thearticles above said predetermined narrow speed range to heat by the highhysteresis properties of said tires; and said speed control meansfurther decreasing the speed of articles within said predeterminednarrow speed range as the weight of the articles increases.
 2. Thegravity conveyor of claim 1, wherein said rolls are each of uniformdiameter and thickness throughout their entire length.
 3. The gravityconveyor of claim 1, wherein said tires have shore durometer hardness offrom 60 to 85A.
 4. The gravity conveyor of claim 1, wherein saidconfining means include opposed side rails substantially parallel toeach other and said support rails, and each of said rails abuttinglyoverlapping, in the vertical direction, each of said rolls and extendingupwardly beyond said pipes a sufficient distance to guide articlescarried on said rolls.
 5. The gravity conveyor of claim 4, including aplurality of vertical axis free rollers mounted in alignment with eachother completely above said rolls and in said side guide rails to extendinwardly therefrom for engaging the sides of articles carried on saidrolls.
 6. The gravity conveyor of claim 1, wherein said confining meansincludes an outer annular groove within each of said rolls at each endthereof and spaced to coincide wIth the spacing of the supporting wheelsso that the wheels riding in the grooves act to prevent lateral movementof the rolls.
 7. The gravity conveyor of claim 6, wherein said sidesupport rails each includes parallel and outwardly horizontally openingU-shaped side channel members mounting therebetween said wheels, and atleast one U-shaped horizontally opening mounting channel receivingtherein one of said side channel members; and elastomeric meanssupportingly between said one side channel and said mounting channel. 8.The gravity conveyor of claim 1, wherein said confining means include anannular flange integrally on each end of each of said rolls, each ofsaid annular flanges extending downwardly to cooperate with one side ofeach of the supporting wheels.
 9. The gravity conveyor of claim 1,wherein said speed control means produces the narrow speed range ofthree feet per minute for a 9,000 pound load and 30 feet per minute foran empty pallet load.